LncRNA FAL1 promotes cell proliferation and migration by acting as a CeRNA of miR-1236 in hepatocellular carcinoma cells

Background: Long non-coding RNAs (LncRNAs) have been demonstrated to play crucial role in tumor growth and metastasis for hepatocellular carcinoma (HCC). LncRNA FAL1 has been indicated to promote the progression of various cancers. However, the role of lncRNA FAL1 in HCC was poorly understood. Methods: The expression levels of lncRNA FAL1 in HCC tissues and cells were determined by RT-qPCR. The roles of lncRNA FAL1 on HCC cells were investigated by MTT, colony formation, transwell, RT-qPCR, and Western blotting. The miRNA binding sites of lncRNA FAL1 was predicted using RegRNA 2.0 and miR-1236 was validated to target lncRNA FAL1 by luciferase reporter assays and RT-qPCR. Finally, the expression levels of lncRNA FAL1 in serum exosome of HCC patients was also investigated and the role of exosome-mediated lncRNA FAL1 was further investigated by co-culturing with HCC cells. Results: This study first showed that lncRNA FAL1 was up-regulated in HCC tissues and functioned as an oncogene in HCC. LncRNA FAL1 could accelerate cell proliferation and metastasis as a ceRNA mechanism by competitively binding to miR-1236. Moreover, lncRNA FAL1 was also up-regulated in serum exosome of HCC patients and could transfer lncRNA FAL1 to HCC cells to increase their abilities of cell proliferation and migration. Conclusions: Taken together, this study indicated that lncRNA FAL1 functions as an oncogenic in HCC and may be a novel diagnostic biomarker or a novel target for the treatment of HCC in future.